Magnetic tape cassette with an improved support liner arrangement

ABSTRACT

A tape cassette is provided with a housing bearing constriction for the hubs and the support liners are provided with curved or bent liner regions which serve both for guiding the empty hub and for aligning and guiding the windings on the hub, in particular the first tape windings to be wound. Practical embodiments of the liner regions differ from one another in that they have different cross-sectional shapes and different arrangements in the longitudinal direction, tranverse direction or both or have a circular shape.

BACKGROUND OF THE INVENTION

1. Field of the Invention

A tape cassette, in particular a magnetic tape cassette, having one ormore tape rolls on an essentially flangeless hub, onto which and/or fromwhich a tape can be wound or unwound in a cassette housing, supportliners having curved or bent liner regions which are coordinated withone another, are opposite one another with respect to the centralcassette plane and can come into contact with the hubs, the tape rollsand the tape temporarily or permanently being provided between the taperoll having tape windings and the bottom and lid walls of the cassette,and an axial bearing constriction being provided between the hubs andthe cassette housing, and the support liners extending at least as faras the bearing constriction, and suitable support liners for such tapecassettes.

2. Description of the Related Art

German Utility Model 8,606,119 discloses a tape cassette whose housingis provided with annular beads in the region outside the hubs. Althoughsupport liners which are likewise bent are used, even minor disturbancesof the tape roll (unevenness) result in Jamming, thus preventingoperation of the cassette.

With the cassette according to German Published Application DAS2,327,828, a certain axial bearing resilience is achievable for the taperoll by virtue of the fact that inner rings projecting beyond the normalend face of the hubs are supported on resilient liner parts locatedabove corresponding housing cavities. However, this provides virtuallyno guidance for the tape roll, so that tape roll and running problemsare not avoided.

German Utility Model 7,221,230 furthermore describes, as bearing meansfor hubs in magnetic tape cassettes, support liners which are locatedopposite one another, have embossed circular rings and are arrangedcoaxially over the hubs but contribute essentially nothing to tape rolland tape guidance.

Finally, German Patent 2,825,457 combined two of the abovementionedpossibilities, the use of a raised bearing edge on the hub and oflongitudinal embossings in the liner which engage the annular groove inconventional hubs, in conjunction with liner regions which are supportedon the housing walls outside the hub diameter. The disadvantage here isthe tape clip present on conventional hubs, which leads toirregularities in the rotation of the hub, which should in fact bebetter guided by the bearing edge and the liner embossings.

Dimensioning the hubs and liner embossings is difficult if it isintended to avoid jamming of the tape roll in all operating states. Thissituation cannot be altered also because a relatively broad liner middlepart which is convex with respect to the housing inner walls and isintended to provide additional resilient support for the hubs isprovided between the liner embossings. Such broad liner middle partdeformations are also very stable here, cannot be produced accuratelyand repeatably in large amounts, are caused to disappear bythermoplastic flow or shrinkage or lose their curvature through adhesiondue to elastic loading on the housing walls and hence lose theireffectiveness. Thus, tape rolls which are step-like and wound in otherirregular ways can still form and lead to the known problems withcassette operation.

It is an object of the present invention better to hold, align and guidethe hub, the tape roll and the tape and to provide tape cassettessuitable for this purpose or suitable support liners for such tapecassettes.

SUMMARY OF THE INVENTION

We have found that this object is achieved by the tape cassettedescribed at the outset, particularly a magnetic tape cassette havingone or more tape rolls on an essentially flangeless hub, onto whichand/or from which a tape can be wound or unwound in a cassette housing,support liners having curved or bent liner regions which are coordinatedwith one another, are located opposite to one another with respect tothe cassette central plane and can come into contact with the hubs, thetape rolls and the tape temporarily or permanently being providedbetween the tape roll having tape windings and the bottom and lid wallsof the cassette, and an axial bearing constriction being providedbetween the hubs and the cassette housing, and the support linersextending at least as far as the bearing constriction, if the bearingconstriction is formed, on the cassette housing, as annular edgeslocated in the region of the inner diameter of the hub, and the curvedor bent liner regions have run-on sections, of which first run-onsections face the particular hub and, for at least parts of its upperand lower outer annular edges, serve for guiding the empty hub and, inaddition to the first run-on sections, second run-on sections areprovided which realign with the hub each of the tape windings to bewound.

We have found that this object is furthermore achieved by support linersfor tape cassettes, in particular magnetic tape cassettes, having one ormore tape rolls carrying tape windings on an essentially flangeless hub,for resting under spring force between the tape roll and the cassettebottom and lid walls, if the liners are provided with curved or bentliner regions which are coordinated with one another, are locatedopposite one another with respect to a central plane and are intended toexert a spring force toward the central plane, and the curved or bentliner regions have first run-on sections which are arranged in theregion of the diameter of the hub and serve for guiding the empty hub,and furthermore second run-on sections are provided outside the regionof the diameter of the first run-on sections, the said second run-onsections realigning with respect to the hub and guiding each of the tapewindings to be wound.

This advantageously results in the curved or bent liner regionsremaining outside the outer diameter of the tape roll and thus beingable to act, in contact along a line, both on the annular and outeredges of the hubs and on the tape windings to be wound, for uniformformation of the tape roll.

In conjunction with the particular annular edge on the cassette housing,the guiding effect of the curved or bent liner regions in the immediateproximity of the hub for the tape and the tape roll is reinforced, sothat tilting and tumbling of the hubs can be substantially ruled out inany operating state without other operating problems, for example due toa projecting tape clip, being more prominent as a result.

In particular, mechanical disturbances (impacts, blows) acting fromoutside on the cassette and also tape irregularities (nonuniform tapethickness over the tape width) are greatly reduced by the novel cassetteembodiment, resulting in a more reliable cassette which functions morereliably in all operating situations.

To support the hub or the hubs without difficulty by means of the curvedor bent liner regions, embossings or bends in the support liners can beprovided in the longitudinal or crosswise direction of the cassette,although it is also possible to use annular embossings.

Regarding the shape of the curved, bent or embossed liner regions,triangular, trapezoidal, circular segments or other arc shapes can beused. In the height with respect to the hub, these liner regions areformed and arranged in such a way that line guidance of the annularedges of the particular hub and for the approaching tape is ensured. Thecurved or bent liner regions coordinated with one another are separatedby a distance which essentially corresponds roughly to the tape width.

It is advantageous, when the cross-sectional shape of the embossings orbends is roughly symmetrical, if the distance from the midpoint of thehub to the symmetry line is greater than the radius of the hub. Thisensures that the hub and the approaching tape windings are subjected tothe same run-on, alignment and guidance conditions and it is not, forexample, just the hub which is guided (as in German Patent 2,845,457).

In the case of support liners resting on the annular edges, the heightof the said liners and the form and arrangement of the curved and bentliner regions are advantageously chosen so that, in the case of a fulltape roll, the said liners do not rest against the inside of thecassette wall in the region of the hub diameter. This ensures that aspring action is constantly exerted on the hub and tape roll in theregion of the outer diameter, both with regard to tilting and tumblingmovements and with regard to any impacts and blows.

It is also advantageous if the axial play between the hub and theannular edges from [sic] housing is from about 0.3 to about 0.7,preferably about 0.5, times the axial play between the tape roll and theinner wall of the housing.

In an advantageous variant of the invention, liner regions which arecurved or bent inside the diameter and are oriented toward the innersurface of the housing are provided in addition to the curved or bentliner regions which lie outside the diameter of the hub.

Consequently, as a result of the additional support inside the hubregion, the spring forces acting on the outer edge can be increased.

The said additional inner curved or bent liner regions can, togetherwith the outer liner regions, have a roughly sinusoidal shape or havethe cross-section of two circular or curved shapes arranged side byside. In practice, the width of the annular edges should besubstantially smaller than the total ring width of the hub, so that acertain angular region is retained for spring support of the hub andtape roll.

According to the invention, this takes sufficient account of alltolerances of the various, interacting cassette parts, which tolerancesoccur in the compact cassette as a mass product and sum in adisadvantageous manner in the extreme case.

The above embodiments and discussions also relate to the support linersthemselves. Details are given in the claims relating to the supportliners themselves and in the description.

BRIEF DESCRIPTION OF THE DRAWINGS

Details of the present invention are described with reference toembodiments shown in the drawings.

FIG. 1 shows an exploded view of a novel cassette

FIG. 2 shows a partial section of a cassette according to FIG. 1, havingnovel bent liner regions

FIG. 3 shows a partial section of a cassette according to FIG. 1, havingnovel embossed circular liner regions

FIGS. 4a to 4g show various schematic support liner embodiments andcross-sectional examples of bent and embossed liner regions

FIG. 5 shows a support liner having transverse bent or embossed lineredges

FIG. 6 shows a support liner having partial embossed liner edges endingat the hub periphery

FIG. 7 shows torque and wow and flutter curves based on measurements, incomparison with a prior art cassette

FIG. 8 shows the support liner embodiment from FIG. 2 as a pair, viewedas a cross-section through the middle.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a compact cassette K having a housing G, consisting of tworectangular bottom and lid walls 1a and 1b and side walls 2a, 2b and 2cor 2d, 2e and 2f, which, when assembled, form an essentially rightparallelepiped cavity 3 for receiving the two hubs 4a and 4b, which arerotatably mounted around axes 5 at right angles to the main walls 1a, 1band inward-pointing bearing edges 7a or 7c and 7b or 7d which surroundorifices 6a or 6c and 6b or 6d coaxial with the said axes. A magnetictape 8 can be wound between the hubs 4a and 4b, where the said tape isfastened at its ends to both hubs 4a and 4b and the tape roll W presenton the hub 4b in the drawing can be completely or partly wound onto thehub 4a and the winding process can then take place in the reversedirection.

A support liner 9a or 9b is located on the inner side of each of thebottom and lid walls 1a and 1b in such a way that by [sic] longitudinal,narrow, parallel, curved or bent liner regions 10 exert a spring forceagainst the end faces of the hubs 4a and 4b, against the tape roll W andagainst the magnetic tape 8 itself.

According to the invention, an additional annular edge 16 is providedaround each bearing edge 7a to 7d of the housing G, of which annularedges 16a and 16b are shown in FIG. 1.

FIGS. 2 and 3 show sectional views of the hubs 4a and 4b, in which eachhub 4 has an outer ring 11 and an inner ring 12 whose axial dimensionsare essentially the same and are slightly broader (by 0.05 to 0.3 mm)than the magnetic tape 8.

The circular orifices of each of the support liners 9a and 9b extendroughly to the bearing edges 7a and 7b, so that, at the inner edge, theyrest on the annular edge 16a or 16b of the housing G.

Here, the parallel, narrow liner regions 10 are in the form of parallelbends 13a and 13b, whose distance from the cassette central axis M isconstant and is chosen so that the parallel bends 13 in contact with,and guiding, the tape 8 and/or the hubs 4a, 4b and/or the tape rolls Ware just outside the outer diameter D of the outer ring 11 of the hub 4,so that the inward-pointing inclined guide surface 14a is in contactalong a line with the outer upper or lower annular edges 15a and 15b ofthe empty hub 4, while the outward-pointing inclined guide surface 14bfaces the approaching tape windings to be wound and is responsible foraligning them and guiding them to the hub.

The smallest distance d between the bends 13 in the immediate proximityof the associated hub 22 (cf. FIG. 4b) essentially corresponds to thewidth b of the tape 8 or is slightly smaller (d≦b), as indicated by adashed line in FIG. 4b.

Because in this case, in the region of the inner rings 12 of the hub 4aor 4b, the support liners 9a, 9b rest on the preferably annular edges 16on the housing G which are arranged around the bearing edges 7, theguiding effect of the bends 13 and of the subsequent, other linerregions which are not shown in detail in the drawing and may also have aguiding effect is further reinforced. The advantageous result here isthat, close to the periphery of the hub 4a, 4b, the guiding effect, inparticular on the tape 8 and tape roll W, is increased, and at the sametime tilting and tumbling of the hubs due to internal and externalinfluences are likewise counteracted from the onset without the windingspace for the tape roll W being inadmissibly reduced.

The inner surfaces of the bottom and lid walls 1a and 1b are denoted by17a and 17b, respectively. The abovementioned liner regions which alsohave a guiding effect and are adjacent to the ends, which are justvisible, of the support liners 9a and 9b (FIGS. 2 and 3) are supportedin some way on the said inner surfaces 17a and b of the housing wall inorder to permit them to have an additional guiding effect on the taperoll W and the tape section running onto its periphery or running offfrom its periphery.

FIG. 3 shows a further embodiment of support liners 9a and 9b havingparallel embossings 18 which have a circular segment cross-section andare provided with run-on, alignment and guidance sections 18a and 18bcorresponding to the parallel bends 13. The circular cross-sectionalform of the embossings 18 can readily be replaced by a curve shapehaving the same effect, for exampel a parabolic shape (cf. FIG. 4c) or asinusoidal shape (cf. FIG. 4g), the functions and advantages beingretained (cf. views in FIGS. 4a to 4g). Furthermore, the triangularcross-section of the parallel bends 13 (cf. FIGS. 4a and 4b) can bereplaced by a trapezoidal cross-section (cf. FIG. 4e) or by a similarform having the same effect. FIG. 4f shows a run-on liner region 21having a liner end 23 which is folded backward or into the diameterregion D of the hub 22 and which is supported in this region on theinner surface 17. The dashed line indicates that in this case a furthersprung support liner 24 may additionally be used on both sides of thetape roll.

All bends, embossings, folds, beads, etc. which can be used for thepurposes of the present invention can be produced in a known manner bysuitable cold or hot forming, depending on the liner material.

FIG. 4g shows support liners having embossings 18, which, however,additionally have circular or curved embossings 19 which are arranged inthe diameter region D of the hub 4a, preferably in the region of theannular groove 20, and are supported on the inner surface 17.

The overall shape may be a sinusoidal shape or may be in the form of twooffset circular segments. In both cases, the hub 4a is given greaterstability and harder spring characteristic by the additional embossing19, depending on the support liner material used.

For example, the dimensions of the individual parts, based on a compactcassette according to DIN 45,516 (June 1976), are given below:

    ______________________________________                                        Width b of the magnetic tape 8                                                                      b = 3.81 mm                                             Axial width of the hubs 4, 22                                                                       h = 3.9-4.1 mm                                                                (.0. 4.0 mm)                                            Axial height of the cassette cavity 3                                                               W.sub.a = 5.0-5.2 mm                                                          (.0. 5.1 m [sic])                                       Thickness of the support liner 9                                                                    n = 0.050 mm                                            Axial height of the annular edge 1b                                                                 h = 0.2-0.4 mm                                                                (0.25-0.3 mm)                                           ______________________________________                                    

The width B of the annular edge 1b in the embodiments shown is greaterthan the width of the inner ring part 12, ie. about 1.5-3 mm, but itmust always be designed to be smaller than the ring width g (cf. FIG.4a) of the hub 12 or 4.

Accordingly, the axial play of the hub 4 between the two support liners9 plus the two annular edges 16 is from about 0.3 to about 0.7 times,preferably about half (factor of 0.5), the axial play of the hub betweenthe inner surfaces 17 of the housing plus the two support liners.

It should be noted that the upper limit of 0.8 is determined by whetherjamming of the hub 4 occurs or is just avoided.

In FIG. 5, in a further support liner 26, the longitudinal parallelbends 10, 13 and 18 have each been replaced by two transverse bends 25for each hub 4 or 22 indicated here.

FIG. 6 shows an embodiment of a support liner 27 having short ornoncontinuous partial embossings 28 to 30, each of which begins at theliner edge but ends in the region of the outer diameter of the hubs 4a,4b and 22. The run-on section for the hub is the particular end of thepartial embossings 27 to 29.

FIG. 8 shows the cross-sectional view of a pair of support liners in theassembled position and the reference central plane ME which, in a tapecassette, is the central plane of the cassette cavity or of the centralposition of the tape roll.

The invention described is based on the observation in the variousoperating states, for example with the development of electrostaticcharges in the cassette or at relatively high temperatures, for exampleduring summer operation in a car, the hubs and the housing generallyundergo less geometric changes (for example due to shrinkage ordistortion) than is the case, for example, with a magnetic tape or taperoll due to stepless layers or loose regions (of tape windings), or dueto distorted roll, hub displacement due to shrinkage and distortion orimpaired guidance properties of the support liner. Hence, the axial playof the hubs in the housing can be readily reduced by the novel annularedges 16 if the tape roll still has sufficient space in the remainingcassette cavity 3 for such disturbances. The novel support liners whichguide and support the tape roll in this cavity can, as already indicatedabove, have different shapes in these regions, as disclosed in manyinstances in the prior art.

Because of the advantageous engagement of the novel bends and embossingswith the annular edges 15a, b of the hubs 4, it is possiblesubstantially to eliminate the serious disadvantage due to the tape clipin the prior art, where a problem arises with each rotation, so thateven projecting tape clips no longer have an effect (cf. curves in FIG.7).

To compare the invention with the prior art, a compact cassette (CC)from Sony, Japan, of Type UCX-S 90 is compared with a compact cassetteof type ChromMaxima® II from BASF AG, under otherwise identicalmeasuring conditions. The CC from Sony corresponds to the cassettedescribed in German Patent 2,825,457, the longitudinal embossings of thesupport liners having in practice an embossing height h=0.3 mm and awidth (distance between the bend edges) of about 2.6 mm, so that theflat support liners were arranged relatively loosely between the innersurfaces of the housing and the tape roll, the embossings, however,having a hard spring characteristic. The embossing height range h offrom 0.28 to 0.53 mm, stated in German Patent 2,825,457, is adjusted byunderlaying with liner strips in the central region of the cassette, asin the BASF CC, in which the curved or bent liner regions pointingdownward and upward had a total height of 0.8 mm, ie. supported the huband tape roll under spring force. The support liner thicknesses were thesame in both CCs.

In both cases of the torque measurement and of the wow and fluttermeasurement, the difference between the theoretical distance d (betweenembossings or bend edges (cf. FIG. 4b)) and the tape width b was plottedalong the abscissa and was varied. The value 0 (zero) thus indicatesthat d=b, ie. there was no longer any play between the tape roll and theinner surface of the housing.

Description of the measurements

In the torque measurement, the winding torque during rewinding of a CCis measured without head contact with the tape. The winding spindle isbraked with a constant torque of 0.08 Ncm. The winding side has analmost full roll and the unwinding side an almost empty one. Themeasurement is made shortly before the end of the tape passage. The CCis in the horizontal position during the measurement. The speed of thewinding spindle is 500 rpm. The measuring apparatus is a torque meter(constructed by BASF AG, Ludwigshafen) and is based on the measurementof the increase in power consumed by the winding motor.

The wow and flutter measurement is a measurement of the fluctuation inthe audio output level of a CC during playback of a recorded signal offrequency 3150 Hz on two different commercial single-capstan recorders,each having two heads. The wow and flutter meter from Woelke, 8069Schweitenkirchen measures the resulting frequency fluctuationsunweighted with a demodulator bandwidth of 1000 Hz. From a large numberof measurements, the ten largest differences are used and the mean valueis calculated using an HP 85 B calculator (from Hewlett Packard). Allmeasured values are represented in a frequency distribution and recordedover the entire tape length.

The curves A are the measured curves for the CC UCX-S 90 (Sony) and thecurves B are those for the BASF CC according to the invention.

The solid curves indicate the measured values of the CC unchanged withregard to the tape clip, whereas the dashed curves show the measuredvalues where the tape clip is displaced by 0.1 mm with respect to theplane of the hub.

    ______________________________________                                        Δ                                                                       (d-b)                                                                         [mm]  0.1         0.15        0.20                                            ______________________________________                                        Md    0.20   (44%)    0.29 (64%)  0.45 (100%) ncd                             [Ncm] 0.20   (40%)    0.28 (56%)  0.4  (80%)  wcd                             W +   0.085  (11.4%)  0.175                                                                              (30.4%)                                                                              0.425                                                                              (73.9%)                                                                              ncd                             F [%] 0.33   (51.5%)  0.40 (62.5%)                                                                              0.44 (68.8%)                                                                              wcd                             ______________________________________                                         ncd = no clip displacement                                                    wcd = with clip displacement                                             

(In the following Table too, the percentages are based in each case onthe initial value:

For A, on the particular value at d-b=0.15

For B, on the particular value at d-b=0)

The result obtained is that the increase in torque rises from 44% to100% even without clip displacement. The increase in the wow and flutterinterference is from about 11% to about 74% without clip displacementand from 51.5 to about 69% with clip displacement.

From the mechanical point of view alone, the prior art CC is notsuitable for trouble free operation on all commercial recorders andcauses the electro-acoustic playback to deteriorate by a half to twothirds if the tape clip projects by only 0.1 mm, which frequently occursin production.

Measurements for CC B (BASF)

    ______________________________________                                        Δ                                                                       (d-b)                                                                         [mm]  0.1         0.15        0.20                                            ______________________________________                                        Md    0               0           0.01        ncd                             [Ncm] 0.03   (6.7%)   0.035                                                                              (7.7%) 0.04 (8.9%) wcd                             W +   0               0           0           ncd                             F [%] 0.025  (4.2%)   0.0375                                                                             (6.25%)                                                                              0.44 (6.7%) wcd                             ______________________________________                                         ncd = no clip displacement                                                    wcd = with clip displacement                                             

It is found that, in spite of a considerable reduction in the springtravel distances of the support liners, there is only a slight increaseof less than 9% in the torque, even with displacement of the tape clip.This tolerance is readily coped with by most recorders, so that thereare no mechanical disturbances during operation of the CC on therecorders.

Even with displacements of the tape clip, wow and flutter aresubstantially below 7%, which, in view of the more difficult conditions(reduction of the spring travel plus displacement of the tape clip)confirms the considerable reliability of these novel support linerembodiments.

A tape cassette is provided with a pair of support liners having curvedor bent liner regions, which essentially act on the outer periphery ofthe one or more hubs and on the first approaching tape windings. In theregion of the inner diameter, each liner can therefore be flat since thegreater lever action at the outer periphery permits centering andstabilization of the rotation. Constriction of the housing bearing atthe inner diameter makes the centering and frictional properties thereindependent of a change in the curve or bend shape of a liner. Hence,support liners and tape cassettes are suitable for all kinds ofcassettes containing support liners and magnetic tape.

We claim:
 1. A magnetic tape cassette of the Philips type whichcomprises: a cassette housing having a bottom wall and an upper wall;atleast one essentially flangeless hub rotatably mounted on an annularbearing edge on said cassette housing, said hub having upper and lowerannular edges above and below its winding surface onto which and/or fromwhich a tape can be wound or unwound in said cassette housing; twosupport liners, each having curved or bent liner regions, said curved orbent regions of said two support liners being coordinated with eachother and located opposite to one another with respect to thehorizontally central plane of the cassette, said liners positioned tocome in contact with at least one hub, with at least one tape roll andwith the tape which is temporarily or permanently provided between thetape roll having tape windings and the bottom and upper walls of thecassette housing, the liner regions serving to guide the tape and formounting the tape roll; an axial bearing constriction providedessentially between the hub and the cassette housing, said constrictionbeing formed on the cassette housing as an additional annular edge andbeing located in the region of the diameter of the hub; said supportliners extending beyond the axial bearing constriction whereby therotatability of the hub is increased, and said curved or bent linerregions having run-on flanks and run-on sections, whereby the run-onflanks face at least parts of the upper and lower annular edges of thehub, thus exerting pressure toward the center of the hub in the radialdirection as well as in the axial direction, thereby centering andguiding the hub when it is empty, and whereby the run-on sections alignwith and guide each winding on the hub.
 2. A cassette as defined inclaim 1, wherein the curved or bent liner regions are embossings orbends in the longitudinal direction of the cassette.
 3. A cassette asdefined in claim 1, wherein the curved or bent liner regions areembossings or bends in the transverse direction of the cassette.
 4. Acassette as defined in claim 1, wherein the curved or bent liner regionsare, in plan view, annular embossings above and below the tape rolls. 5.A cassette as defined in claim 1, wherein the run-on flanks areconstructed as run-on bevels.
 6. A cassette as defined in claim, 1,wherein the cross-sectional shape of the embossings or bends is a shapefrom the group comprising a triangle, trapezoid, circular segment orarc.
 7. A cassette as defined in claim 6, wherein the cross-sectionalshape of the embossings or bends is roughly symmetrical and the distancefrom the midpoint of the hub to the symmetry line is greater than theradius of the hub.
 8. A cassette as defined in claim 1, wherein thecurved or bent support liner regions coordinated with one another andlocated opposite one another are separated by a distance whichcorresponds roughly to a tape width.
 9. A cassette as defined in claim1, wherein the support liners resting on the annular edges, the heightand width of the annular edges and the form and arrangement of thecurved or bent liner regions are chosen so that, with a full tape roll,the support liner does not rest against the inside of the cassette wallin the region of the hub diameter.
 10. A cassette as defined in claim 9,wherein the axial play between the hub and the annular edges on thehousing is about 0.3-0.7 times the axial play between the tape roll[sic] and the inner surfaces of the housing.
 11. A cassette as definedin claim 9, wherein the axial play between the hub and the annular edgeson the housing is about 0.5 times the axial play between the tape roll[sic] and the inner surfaces of the housing.
 12. A cassette as definedin claim 1, wherein liner regions which are curved or bent and arrangedinside the diameter of the hub and are oriented toward the inner surfaceof the housing are provided in addition to the curved or bent linerregions which lie outside the diameter of the hub.
 13. A cassette asdefined in claim 12, wherein the cross-sectional shapes of both linerregions, within and outside the diameter of the hub, together is [sic]roughly a sinusoidal shape.
 14. A cassette as defined in claim 12,wherein the cross-sectional shapes of both liner regions, within andoutside the diameter of the hub, together are roughly two circularsegment shapes adjacent to one another.
 15. A cassette as defined inclaim 1, wherein the width of the annular edges is substantially smallerthan the ring width of the hub.